


and when you need space to breathe, i'll leave (but who needs space from across the country?)

by Czernyandlynch



Category: Harry Potter - J. K. Rowling
Genre: Because I am the best possible friend on the gd planet, But when my BFF asks for a self insert HP fic I write it, Duelling Club, F/F, F/M, GET READY FOR SOME, I DONT MAKE THE RULES, ITS CRACK, Look I won't apologize for this, Multi, Oh my god they were quarantined, Yearning, a prank war, and they were quarantined, castien's bunnies are OCs, duelling club but make it SEXY, friends to rivals to lab partners to friends to lovers, gay dads harry and draco potter-malfoy, im ashamed, magical flu?, quidditch romance
Language: English
Status: In-Progress
Published: 2020-05-27
Updated: 2020-07-19
Packaged: 2021-03-02 21:41:20
Rating: Not Rated
Warnings: Creator Chose Not To Use Archive Warnings, No Archive Warnings Apply
Chapters: 2
Words: 5,212
Publisher: archiveofourown.org
Story URL: https://archiveofourown.org/works/24413764
Author URL: https://archiveofourown.org/users/Czernyandlynch/pseuds/Czernyandlynch
Summary: When Castien Potter-Malfoy boards the Hogwarts Express for his seventh year, he's excited. He's nervous. He's a lot of things, but most importantly, he's determined to make his last year at Hogwarts a year to remember. With his best friends Foxglove and Gingko by his side, he knows that nothing can stop him as he studies for NEWTs and plays harmless pranks on the population of Hogwarts School of Witchcraft and Wizardry.But when his childhood rival who disappeared mysteriously during Castien's fourth year returns to finish out her Hogwarts education, Castien's plans find themselves in disarray. Her reappearance in his life reignites their rivalry and brings back so many memories...except the one that would explain why they are rivals in the first place. Not to mention, Foxglove's growing preoccupation with Eira Cadigan may cause some trouble on the quidditch pitch, and Gingko's mysterious absences from the common room are starting to be noticed.or; the friends to rivals to reluctant group project partners to friends to lovers we (Castien and I) always wanted!
Relationships: Draco Malfoy/Harry Potter
Comments: 4
Kudos: 26





	1. I gotta get back to Hogwarts! I gotta get back to school!

The morning came over Godric’s Hollow as it always did, beautiful and golden, and slowly, the small village began to come awake - except for Castien Potter-Malfoy, who had restlessly awoken before dawn and was already camped out in the kitchen, making breakfast. He knew, of course, that his dad would be downstairs soon and that he made better bacon, but Castien was looking for something to distract him. You see, today was the day: September 1st. The first day of his Seventh year of Hogwarts, and the last time he would journey to Kings Cross Station to board the Hogwarts express.

Castien was a bit overwhelmed by it all.

Castien was also burning the bacon.

  
“Merlin’s pants!” he exclaimed, switching the burner off and setting the skillet down on a cool part of the stove, rushing to open the bay windows and fan the smoke out before the muggle fire alarm his dad had insisted on installing went off - but it was too late. The blaring alarm rang through the air, accompanied by the monotone voice of a heavily accented woman.

  
_“PLEASE EVACUATE”_ the alarm screamed. “ _PLEASE EVACUATE IN AN ORDERLY FASHION._ ”

  
Castien winced as his father began shouting incoherently from the upstairs master bedroom.

  
_“CASTIEN,_ ” his father shrieked.

“YES FATHER?” Castien shouted back, hoping that maybe, just maybe, if he sounded unconcerned enough, his father would match his mood. The wooden kitchen chair made a grating noise as Castien grabbed it from the breakfast table and dragged it across the tile, positioning it under the fire alarm. He reached up to unscrew it and pop the batteries out as quickly as he could, but - his fingers just grazed the bottom of it. He cursed. Too short.

  
_“PLEASE EVACUATE IN AN ORDERLY FASHION”_ shrilled the alarm. _“PLEASE EVACUATE.”_

  
“TURN THAT BLOODY THING OFF OR SO HELP ME MERLIN I’LL-”

  
Castien jumped as high as he could and smacked the alarm with his fist. It broke off from the ceiling and shot out the window he had just opened into the back garden, taking its obnoxious pleas for evacuation with it.

  
Castien looked around guiltily as his parents thudded downstairs. _At least,_ he thought, _I have successfully distracted myself._

  
Harry and Draco Potter-Malfoy appeared, disheveled, at the bottom of the stairs, looking around the cozy kitchen in disbelief. Well, that is, the Potter half of the pair was disheveled. Draco would never deign to appear anywhere in a state remotely resembling disheveled, and if Castien looked closer, he could see that his father had taken the time to put product in his hair before coming downstairs. His obsessive hair care aside, no amount of product could distract from the grumpy look on the man's face. The Malfoy half of the Potter-Malfoys was best not awoken before nine in the morning, and with a glance to the clock on the mantle, Castien could see that fortune was not in his favor. 7:10 am.

  
Ah well. He had had a good life.

  
Castien’s father raised a trembling finger, pointing it at his son. “What is the meaning of this infernal racket?” he demanded.

  
Castien looked around, making eye contact with his dad, hoping that perhaps the savior of the wizarding world would come to his son’s rescue. His hope was in vain. Harry shrugged and shouldered past his grumpy husband, snickering quietly while he put on the kettle for tea.

  
“I made bacon?” Castien supplied, gesturing to the blackened skillet.

  
In the garden, the distant cries of the alarm continued.

  
Draco looked around the kitchen with despair in his eyes. “Huh.”

  
He went to the small kitchen table and slumped over it, head on his arms, snoring gently until Harry brought over a steaming mug of tea which rather miraculously revived the pale man.

  
Castien shrugged. His father had always been rather overdramatic. He went to the cabinet and brought out the bread to make some toast.

* * *

The Hogwarts Express gleamed in the morning light, the steam which circled the platform catching and refracting the light like a dream. Castien stood with his cart, laden with his trunk, and willed the moment to stay in his memory forever. He felt, behind him, his parents coming up to each place a hand on his shoulders.

  
“Are you excited for your seventh year?” His dad asked, looking over at the Express with a nostalgic expression. Castien grinned. “I’m beyond excited, Dad, I just…”  
“Not ready for it to be over, huh?” His dad finished his thought for him. Harry pulled Castien into a hug, squeezing his son tightly. “It’s never really over, kid. Hogwarts can always be your home.”

  
Castien saw the shininess of his dad's eyes and smiled a bit more. “I’ll miss you both.”

  
Draco looked at his son and pulled him in for an embrace as well, much more comfortable with these public displays of affection than he had been Castien’s first year.

  
“I know you’ll do us proud, Castien. You’ll be winning the House Cup for Slytherin again, and you will write to us so often that it will be like we’re there with you.” Castien laughed at his dad’s disgusted expression at the thought of a win for Slytherin, but his father shook a finger at him.

  
“That’s not optional!” He intoned rather sternly, but Castien saw the amusement in his eyes. “Now,” Draco looked around, “where are those troublesome friends of yours?”

  
Castien cast his gaze around the station but the platform was obscured by the mist. He shrugged, explaining that “it's always easier to meet in our compartment. I’ll see them when I board the train.”

  
“Well then,” His father patted him on the head. “You have a good year, son.”

  
Harry laughed at his husband’s awkwardness and gave Castien one last hug. “We love you, kiddo. See you for the holidays!”

  
“I love you! You too, Father!” Castien waved at his parents and took the handles of the car, pushing it towards the express and disappearing into the clouds of steam that had settled on the train platform.

  
As he hefted his trunk onto the train he couldn't help but feel that this year was going to be one to remember.

* * *

Castien could hear Foxglove before he saw her, and followed the faint sound of her most recent diatribe to the compartment she and his other best friend, Gingko, had staked out against the wave of younger students who were desperately looking for compartments of their own. As he pushed the door open and hefted his trunk up onto the rack, Foxglove barely spared him a nod.

  
“- and then, can you believe this, she carried on through the shop like I wasn’t there! Just a wave and a smirk - she _smirked_ at me, Gingko, and then what? Nothing! Collected her school books and went to the register like she owned the place! The sheer audacity of this girl, I swear, with her _hair_ and her _attitude_ , smirking at me, and - oh! She passed me on the way out, you know, and do you know what she said?”

  
Gingko, who was stretched out on the bench opposite the small but loud Chaser, sighed.

  
“What in Merlin’s name did she say, Foxy?” The question was muffled by the copy of the Daily Prophet abandoned over the man’s face. He projected an aura of defeat, as anyone who had been subjected to Foxglove’s unceasing attention tended to do. Castien took a seat beside her and she threw her legs over his lap, acknowledging his presence.

  
“Castien! Good of you to join us! Listen, she said - well, she passed me and stopped, of course, and then said, ‘see you at school’ to which I responded, ‘suppose you will,’ because what sort of inane thing is that to say, ‘see you at school’ - of course you will, we have classes together, for Merlin’s sake!”

  
Gingko sighed, but there was more.

  
“But then she smirked - again! What is with this witch, honestly! With the smirking, you’d think she's a Slytherin, the way she carries on, sly glances and the smirking, its _indecent_ , what sort of Ravenclaw acts like that? And anyway, she leaned over and tapped the book I was holding, the Defense one for this year, I’m doing the NEWT course, obviously, and she told me I should come “check out the Duelling club”! What on Earth could she mean by that? Who does this witch think she is?”

  
Gingko groaned and lifted up the corner of the Prophet covering his face, making long suffering eye contact with Castien. “For reference, she’s talking about Cadigan, again.”

  
“Oh really?” Castien shot a glance at Foxglove, who scowled. Inwardly, he was laughing. It was good of Gingko to reference Eira Cadigan as if Castien might not be sure who the subject of Foxy’s rant was, when in reality poor Foxy had been maintaining a slight obsession with her redheaded rival chaser since they both made their respective house quidditch teams second year.

He raised an eyebrow at her and she huffed, “Yeah, she’s annoying. Can’t believe we have to work together again this year, she’s the Ravenclaw captain and don't get me wrong, the girl can fly, but the way she drills evasive maneuvers seems to me-”

  
Castien leaned back onto the bench seat and let Foxglove’s voice wash over him. This year would be a good one, he decided, and maybe he and Gingko could push Foxglove into doing something about the crush she clearly had on the Ravenclaw girl.

  
As the train sped towards Hogwarts and the shadows collected outside their compartment window, they pulled their robes on and played a few hands of exploding snap, in which Gingko completely destroyed the other two, and demolished the candies they had bought off the trolley. When the Express pulled into the station, the three friends made eye contact with each other.

  
“Let’s make this a year to remember,” Castien grinned at Foxglove and she rolled her eyes.

  
“You're such a sap,” she huffed, but she leaned over and ruffled his hair and Gingko laughed at her. “Don’t act like you aren’t secretly making that scrapbook, Foxy. We’ve all seen it and it’s very cute.”

  
Foxglove pushed him on his way out of the compartment and he laughed, dodging her efforts to trip him up all the way to the carriages, which Castien knew were pulled by invisible horses but to him always seemed like pure magic.

* * *

Castien sat sandwiched between Foxy and Gingko at the Slytherin table during the Welcome Feast. The sorting had been good this year, with a decent number of new Slytherins joining them at the table, and food had been, as always, excellent. He sat back rather sleepily as McGonagall stood and walked to the podium for the Headmistress address.

  
She gracefully gave the usual announcements, ones that had been the same since he was a tiny and terrified first year and that his dads had assured him had been the same when they attended Hogwarts as well. Castien thought about the Weasley’s Wheezes products he had stashed in a hidden compartment in his trunk and idly planned for ways he could make good use of the contraband - letting off steam during NEWT year was vital, after all.

  
McGonagall explained the typical Hogwarts bans on having fun and fighting in the corridors, the House Cup and points and Quidditch. Castien tuned back in to hear her say,

  
“And finally, the Forbidden Forest is just that - _forbidden_.”

  
He wouldn’t say that she made eye contact with him, but he wouldn’t deny it, either. He noticed that she also turned and cast a stern look at the Gryffindor table, where several redheads sat looking perfectly, incredibly innocent. He smirked at Fred and Roxanne Weasley, his cousins of a sort, and their innocent expressions turned wicked as they grinned back at him. Though they were a sixth and fifth year, respectively, they had learned quite a bit from their dad and were always fun to plan a few pranks with during the year.

  
“Stay out of the forest unless you have written permission from a professor and an escort.” McGonagall emphasized, and continued,

  
“Welcome, of course, to our new first years. Hogwarts is pleased to have you amongst us, and I know you will do your new houses credit. To our returning students, welcome home. To our students who have been gone from us for a time, Hogwarts is pleased to have you back. And to the sixth and seventh years who will be taking their OWLS and NEWTS and looking forward to the future, good luck. Have a goodnight, everyone, and I will see you all bright and early tomorrow for the beginning of classes.”

The Prefects and Heads of Houses stood up and began herding the sleepy-looking first years to their respective common rooms, and Castien stood and leisurely stretched, blinking at Foxglove and Gingko as they sat and looked at him expectantly. He turned and looked over his shoulder at the Great Hall, which was slowly emptying of students, many loitering to catch up with friends they hadn’t seen on the train, then back at his friends

  
“What are you two looking at?”

  
They looked at each other and back at him.

  
“Wait, are you saying you didn’t notice?” Foxglove said, fighting the rather evil smile that was creeping onto her face. Castien was deeply regretting the choice the Sorting Hat made years ago, because Merlin, having Slytherin friends was a lot to deal with sometimes.

  
“You didn’t catch that bit of the speech mate?”

  
Castien laughed. “The bit about the forest? It’s always forbidden, but it’s not like that's ever stopped us, has it?”

  
Foxy smirked at him. She has no right to complain about Cadigan smirking at her, Castien thought, when that's basically her only facial expression.

  
“McGonagall made a point to welcome back students who had been away from Hogwarts for a time, Castien. Who do you think that is?”

  
Castien froze. “Wait, what are you saying -”

  
A laugh from the other side of the Great Hall cut him off. Castien whips his head around to watch as two girls, a brunette and a redhead, both wearing Ravenclaw robes, walk towards the exit of the Great Hall. The girl on the left tilts her head back, cackling at whatever the redhead has said to her, and Castien can only see a glimpse of her profile across the room but he knows who it is in an instant. If he’s honest with himself, he knew the moment he had heard that laugh cut across the room like a knife.

  
“Ah, well, I forgot she and Cadigan were quite close through fourth year.” Foxy huffs and glares at the redhead leaving the hall. Gingko looks at Foxglove and then at Castien, who are both staring at the backs of the retreating pair. He sighed.

  
“This is going to be quite an interesting year, isn’t it?”

Castien walked with his friends down to the dungeon in a kind of daze, ignoring their bickering while his brain hyper-focused on a certain student’s return to Hogwarts. It just didn’t make any sense, he thought.

  
Ruth Blickenstaff had vanished midway through their fourth year.

She was in Potions and Transfiguration and Charms one day, taunting him incessantly, and then _gone_ the next. No letter, no explanation, just gone. A halfhearted explanation from Flitwick about “family troubles” back in France.

Why did she come back? Why now?

Castien wished Foxglove a distracted goodnight, ignoring the exasperated look she tossed his way, and made his way with Gingko into the seventh year boys dorm, falling into a heavy sleep.

* * *

**Notes for the Chapter:**

> If you read this and you're not Castien, I'm sorry. The fire alarms are based on something that happened to me this semester, when i forgot to turn on the ventilation while cooking and discovered the smoke alarm in my new house actually very bossily instructed us to leave the house in a British accent.  
> Also: Don't write fic about real people unless you have their express permission. Come on ya'll, it's weird.


	2. I gotta get myself to Hogwarts, where everyone thinks I'm cool! (except, maybe one person)

**Summary for the Chapter:**

> Castien attempts to make it through his first day of classes without incident and nearly manages it

Castien has long since decided that waking up at Hogwarts is one of his favorite ways to start his mornings. The Slytherin dorms, which his dad always described as being cold and formal (which he had only seen once during his illegal escapades his second year) had been updated post-war, and Castien found the low, wavy light that filtered in from the lake to be peaceful. He got dressed in his uniform, tying his Slytherin tie loosely around his neck as he grimaced at the morning chill. Nice or not, there was no getting past the chill of living in the dungeons.

Socks muffled against plush, layered floor rugs, Castien crossed the dorm to wake Gingko.

“Get up, mate, it's time for breakfast!” Castien swept the drawn curtains aside and found his friend's bed empty. _That’s odd_ , Castien thought, glancing at the clock, which told him that it was a quarter after nine- if it was telling the truth. Sometimes they didn’t, at Hogwarts. Something about the effects of residual magic. _I’ve never known Gingko to wake up a moment before he needs to._ His bag was absent from his desk too, so Castien shrugged, deciding he must have gone to breakfast early. _He’s probably just as excited about the start of term as the rest of us._

Castien grabbed his bag and toed his shoes on, making his way out of his room and through the common area, waving at some sleepy sixth years he knew vaguely. The walk to the Great Hall was quick, in part due to a secret passage behind a tapestry of a hunting scene that he had found in one of the lesser-used dungeon corridors. He’s pretty sure his dad didn’t know about it either, which was gratifying. Castien liked the idea that maybe he was the only one who knew about the passage, that it was a secret he and Hogwarts could share. He was greedy that way.

Castien walked through the double doors of the Great Hall, surveying the different house tables. He waved good morning at a seventh year Hufflepuff that had been his potions partner last year as he passed their table and collapsed next to Foxglove at the Slytherin table. She didn’t look up, too busy jamming oatmeal and bananas into her mouth, but she leaned against him in greeting, which was generally more acknowledgment than he got from her at mealtimes.

“Morning! Have you seen Gingko?” The third member of their trio was notably absent from his usual spot across the table. Foxglove shook her head, swallowing her mouthful of oatmeal and taking a gulp of her tea. “He hasn’t come up for breakfast yet, I thought he was with you.” Castien shook his head and started loading up his plate. “Nope,” he said “He was gone when I woke up. Maybe he’s gone to see a professor before class starts?” Foxglove shrugged and took another bite of oatmeal. “Either way, we’ll see him in Herbology. You’re taking it for a NEWT, right? Have you got your schedule yet?”

Castien nodded, spreading the parchment with his schedule on it out on a clean spot of the table for her to peruse. “Oh, this is a pretty good one! You just have your independent study when I have Ancient Runes- and I think Gingko is taking Arithmancy during that block.”

“Perfect. Thank Merlin none of us are starting too early - the second years all have Transfiguration at 8:30.” Foxglove gagged dramatically. “That sounds absolutely hellish.” She checked her watch and scraped up the last bite of oatmeal onto her spoon. “Shall we? I wouldn’t want to be late to go stare at seed pods.”

“To the greenhouses we go! My lady,” Castien stood and offered her his arm. She accepted with a haughty nod. “Good sir,” she intoned as they traipsed out of the Great Hall to Herbology.

* * *

Castien enjoyed Herbology quite a bit but could admit privately to himself that he preferred the days when he didn’t leave the greenhouses with his hands covered in dirt. _It’s even caked under my fingernails_ , he grumbled at the sinks before lunch, shoulder to shoulder with several Hufflepuffs with whom the Slytherins shared the class. Even with a baby boom post-war (which admittedly Castien was a product of) classes at Hogwarts still tended toward the smaller side, especially at the NEWT level.

Washing up for lunch, he reflected on his first class of the term. It had been fun to be in Herbology again with Gingko and Foxglove, working at one of the greenhouses' big tables with a Hufflepuff called Jackson to round out the group. They had set up an experiment meant to run until the winter holiday, but raising Venomous Tentacula from a seed pod was always an unsure and dangerous endeavor, so around Yuletide, the group would reevaluate their progress and go from there. Castien left the washroom and crossed the corridor to the Great Hall, heading towards his customary seat at the Slytherin table. Gingko was there, finally, he noticed, across from Foxglove...and across from some stellar looking sandwiches.

Castien sat and started gathering together his meal while Foxglove tried to draw him into a conversation about her quidditch lineup. She had managed, in the ten minutes they had been separated between the Greenhouses and the Slytherin table, to corner several prospective third years about playing, and drawn up an ambitious looking practice schedule which she was debating loudly with herself.

Tryouts were Friday, and Castien was already desperate to see them finished.

“Okay, so, if Atticus is a sure thing, which she is - stellar beater, absolutely _wicked_ arm - then I can pencil her into this strategy as long as I work with her on maneuverability, which - oh that means we’ll have to push for the 5:00 start time for practices, especially if we’ll have to train any new players in our drills…which we might, if those third years were serious...rather flaky, third years are...”

“Five?? Five in the morning?” Gingko sputtered, putting down his Arithmancy textbook. “Foxy, it’ll be freezing that early in the mornings, especially in a few weeks. That’s ridiculous.”

Foxglove narrowed her eyes, staring her friend down with an intensity reserved for absolutely batshit seventh-year quidditch captains.

“Gingko, I know for a fact that you aren’t questioning my training schedule.” He gulped. She continued, “If there’s a single player on my team who isn't working hard enough to keep warm, they better be smart enough to manage a warming charm because we don’t simply show up at 5 am: We. Are. In. The. Air.”

Ginkgo's eyes were wide and terrified, as anyone would be if they were confronted by Foxglove in a sports frenzy.

“Yes ma’am!” he saluted. Castien gulped as she turned to him and pointed her finger level with his nose.

“Do you have anything to add?” He shook his head. Rapidly.

“No! Of course not. Five in the morning sounds generous. Reasonable, even.”

Foxglove nodded and, with a "Hmph!" returned to her quidditch plans.

“Speaking of early mornings, Gingko, where were you today? We missed you at breakfast.”

Castien nudged Foxglove and she distractedly agreed, “Mhm!” Gingko shrugged and took a bite of his soup, checking his notes as he did.

“Had a meeting before breakfast with the new Arithmancy professor. Not a big deal, but it ran long. You know how they do.” Castien nodded, biting into his sandwich. They didn’t have too long before lunch was over and had to make their way to Potions which was a mixed block for the Seventh years - it would be a pretty small class then.

Castien had heard that it would be primarily practical, with a lot of independent brewing, which he was rather excited about.

* * *

_Everything will be fine_ , he thought later, as he walked down to the dungeons along with Gingko and Foxglove, already primarily preoccupied with the meeting he would have after Potions.

His seventh year allowed him to arrange an independent study, and Castien had spent his summer working towards his post-graduate plans: a magical painting apprenticeship with one of the most renowned portrait artists in Britain.

Sally Herdan was a household name and it had been pure luck that she had reviewed his portfolio - she wasn’t planning on taking on an apprentice, she had said. But she had agreed to an interview anyway, and had helped him design an independent study in the history of magical art. Castien was determined to impress her, knowing that this could be his key to his dream.

But first: potions class. The trio waltzed into the underground classroom, early enough to have their pick of the sturdy brewing tables. They set up their stations with practiced ease as the professor wrote a couple of notes on the board. Professor Tally was a tall, older witch who had begun teaching at Hogwarts in Castien’s second year, and her no-nonsense attitude extended from potions making to pretty much everything else in life. Castien had learned early on to not cause too much trouble in her dungeon domain.

The classroom began to fill with a few more students, a group of three Hufflepuffs followed by a pair of Gryffindors, and - He felt Foxglove draw up straight beside him as Eira Cadigan led a group of several Ravenclaws into the class, and next to her… Ruth Blickenstaff claimed a spot at the brewing table immediately in front of him - _at the front of the classroom, of course, typical Ravenclaws_ \- She tossed a long brown braid over her shoulder as she unpacked her brewing gear, pulling out her textbook as Cadigan settled in next to her, their heads tilting together as they whispered in low tones.

Castien jolted as Foxy drove her elbow into his side because for a tiny witch she had some sharp elbows.

“She’s not even going to say hello! Can you believe that?” she hissed into his ear, her eyes boring holes into the back of Cadigan’s head.

Castien shook his head, unable to tear his eyes away from the pair of Ravenclaws. Irritation boiled low in his stomach as Professor Tally stepped in front of the board and welcomed them to the first class of the term, immediately beginning to lecture about Everlasting Elixirs and their importance. Castien couldn’t bring himself to shift his attention to the front of the room as Blickenstaff started taking notes, her book angled weirdly to keep ink from smearing against her hand, her own weirdly sharp elbow nudging against Cadigan, who sat on her left.

“...For your NEWTs this year, we’ll be working towards perfecting a few new potions, such as Amortentia and Felix Felicis, and several Draughts, which you will then preserve with an Everlasting Elixir. It’s essential that the Elixir is brewed to perfection, or your base potion can spoil and you’ll have a hell of a time figuring out which ingredient has gone bad...”

Castien’s eyes focused on a scrap of paper that Blickenstaff scribbled on, tearing off the corner neatly and smoothing across the table. Cadigan accepted it neatly, lifting the edge of her textbook to cover it from Professor Tally’s view. _Who does she think she is,_ Castien huffed, _passing notes in the front row like that?_

"Now, when creating your Everlasting Elixir, it’s vital that you’re well versed in the intricacies of the potion that it’s meant to preserve. An Elixir to preserve a Draught of Living Death will not work for an...Elixir to Produce Euphoria, let’s say. Does anyone know why this is?”

Cadigan raised her hand. Foxglove grumbled next to him. He felt rather than saw Gingko roll his eyes at her sullen behavior regarding the Ravenclaw.

“Yes, Miss Cadigan?”

“Isn’t it because one needs to account for the particular ingredients of a potion? Porcupine quills are used in the Elixir to Produce Euphoria, and they can be preserved by adding powdered lacewing flies to an Everlasting Elixir. But if you added lacewing flies to a Draught of Living Death, even in an Elixir, the whole thing would blow up.”

Professor Tally nodded, pleased. “Exactly, Miss Cadigan. Five points to Ravenclaw for a thorough answer and coming into class prepared. Can anyone tell me why adding lacewing flies to a Draught of Living Death would cause it to ‘blow up’, as Miss Cadigan put it?”

Foxglove scoffed quietly.

Castien raised his hand.

“Miss Blickenstaff?”

The girl in front of him lowered her hand. Castien fumed.

“It’s due to the interaction between the lacewing flies and valerian root, ma’am. Lacewing flies are meant to bind things together, working best when they can create two halves of a whole. Valerian root is a sedative, but an unstable one. If it’s bound to the wrong ingredient, the effects can be explosive.”

Castien frowned. She wasn’t wrong, but what a strange way to talk about ingredients in a potion. Two halves of a whole?

“Hm, thank you, Miss Blickenstaff,” Professor Tally turned to scribble a note on the board about ingredient pairings. “A bit philosophical, but very correct. Another five points to Ravenclaw, and it’s very good to have you back in my classroom. So clearly, it’s not a one size fits all equation. One must know very intimately the preparation and ingredients of particular potions, and beyond that, Everlasting Elixirs are infamously tricky to prepare. They can take a whole moon cycle to be ready to add to the potion of your choosing, and for that reason, we’ll be working on them throughout the year even as we become experts in more advanced potions...”

Castien jotted down a few half-hearted notes about Everlasting Elixirs as the lecture came to an end and Professor Tally instructed them to begin brewing a simple calming draught to warm up after the summer.

Just because Ruth Blickenstaff had decided to return to Hogwarts, and to sit in front of him, not even acknowledge him - she thought she was better than him, didn't she - he wouldn’t allow himself to fall behind in Potions, of all things. In any of his classes.

This was going to be Castien’s year, and no arrogant, weird, know-it-all Ravenclaw would ruin it for him. He had grown up while she had been off who knows where, and whatever petty rivalry they had been stuck in since their first year, well, Castien was determined to step above it. If she was going to ignore him, he could ignore her back. He could ignore her _better_.

Class ended with a shuffling of papers and robes and Professor Tally promising to see them at the same time on Wednesday, but only after they had read the chapter on Golpalott’s Third Law, of course. Gingko slapped his shoulder as he gathered his books and made his way out of the classroom ahead of him. Castien looked to Foxglove as she shoved some loose papers in her bag, covered in weird circles and lines and whatever made-up sports stuff helped her win matches. She was staring at Cadigan as she cleaned up her station, chatting with her friend.

Blickenstaff scrunched her nose up as she talked. _She should stop that_ , Castien thought unwittingly. _She looks like some kind of rabbit._ The two Ravenclaws turned to leave the classroom in a swirl of blue robes and general snobbery when Blickenstaff turned her head to glance at him over her shoulder.

Their eyes met, and when she caught him staring, the corners of her mouth curled into a smirk.

The two girls disappeared into the corridor.

**Notes for the Chapter:**

> Hello and thank you so much to everyone who read and left kudos or a comment on my dumb fanfiction!! Ya'll are very sweet and I hope you enjoy this silliness :)


End file.
